A method of asymmetric asynchronous decoupling of capacitors in an integrated circuit design is provided for faster simulation by circuit simulators, e.g. FastSPICE circuit simulators. This method includes removing a coupling capacitor from a list, which includes coupling capacitors that capacitively couple two nets in the design. The two nets have capacitances C1 and C2, and at least one of capacitances C1 and C2 exceeds a threshold. The coupling capacitor has capacitance Cc. When coupling capacitance Cc is low and only one of capacitances C1 and C2 has a low capacitance, then a forward capacitance can be used at whichever of the two nets has the low capacitance and a lump capacitance can be used at the other net for simulation. When coupling capacitance Cc is low and both of capacitances C1 and C2 have high capacitances, then lump capacitances can be used at the two nets for the simulation.